Details

Autor(en) / Beteiligte

• Yu, Tong
• Wang, Bin
• Yu, Li‐Ping

Titel

Dual‐mode color‐changing pH sensor based on fluorescent MOF embedded photonic crystal hydrogel

Ist Teil von

• Journal of the Chinese Chemical Society (Taipei), 2022-05, Vol.69 (5), p.831-839

Ort / Verlag

Weinheim: Wiley‐VCH Verlag GmbH & Co. KGaA

Erscheinungsjahr

2022

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• In this work, a novel pH‐responsive hybrid hydrogel namely MOF/PC hydrogel was prepared by incorporating metal–organic framework CDs@UiO‐66(OH)2 into the matrix of photonic crystal hydrogel. MOF/PC hydrogel could display colorful structure colors under visible light and emit blue fluorescence under UV light owing to the stop‐bond effect of photonic crystal and fluorescence emission capacity of CDs@UiO‐66(OH)2, respectively. Benefiting from these two optical phenomena, MOF/PC hydrogel could work as a dual‐mode color‐changing sensor, in structure color mode and fluorescence mode, for the sensing of pH. When incubating in aqueous solutions with different pH values, MOF/PC hydrogel could adjust its structure color to the corresponding one ranging from green to pink in 10 s, and this visible color‐changing can be used to determine the approximate pH values of the sample by naked eyes without any assistance of instruments. As for the fluorescence mode, the fluorescence intensity of MOF/PC hydrogel showed a good linear relationship with pH value in the range of 3.0~7.0, and it can be used to determine the pH value of aqueous solutions quantitatively. Moreover, the as‐prepared sensor is reusable and can be applied to the pH sensing of real water samples. Novel dual‐mode color‐changing sensor (MOF/PC hydrogel) was achieved by taking advantages of the stimuli‐responsive color‐changing ability of photonic crystals and the sensing performance of luminescent MOF. When immersed in pH solutions, the structure color of MOF/PC hydrogel changed quickly, and its fluorescence intensity showed good linear relationship with pH, both ensuring the visual and quantitative pH sensing.